1. Field of the Invention
This invention relates to an inflator for an air bag, and more particularly, to the type of inflator known as a hybrid inflator.
2. The Related Art
Many types of inflators have been disclosed in the art for inflating an air bag for use in an inflatable restraint system. One involves the utilization of a quantity of stored compressed gas which is selectively released to inflate the air bag. Another derives a gas source from a combustible gas generating material which, upon ignition, generates a quantity of gas sufficient to inflate the air bag. In a third type, the air bag inflating gas results from a combination of stored compressed gas and a gas generating material. The last mentioned type is commonly referred to as an augmented gas or hybrid inflator.
Hybrid inflators that have been proposed heretofore are subject to certain disadvantages. They require glass-to-metal-seals or other complex sealing methods to maintain the high pressure seal and/or require an actuation means (mechanical or pyrotechnic) to open the flow passages to the air bag. Many hybrid inflator arrangements dispense cold inflating gas followed by heated gas. This is a disadvantage for an air bag driver system. Additionally, end diffusers typically used on hybrid inflators make packaging in modules difficult.
Thus, there is a need and a demand for improvement in hybrid inflators to the end of overcoming the foregoing disadvantages. The present invention was devised to fill the gap that has existed in the art in these respects.